Swap standalone snapshot for Mysql 8 => 5.7

[ufundo]

Standalone upgrade test fails on php74m57 because newly added snapshot was dumped from Mysql 8, and can't be restored to mysql 5.7 server.

Swapping for a Mysql 5.7 dump.

[ufundo]

Old snapshot doesn't work, new snapshot does:

Using 'databases_standalone' snapshot library for Standalone
/home/ufundo/Code/civicrm/civicrm-buildkit/vendor/civicrm/upgrade-test/databases_standalone/5.77.0-standalone-clean-mysql57.mysql.bz2
/home/ufundo/Code/civicrm/civicrm-buildkit/vendor/civicrm/upgrade-test/databases_standalone/5.77.0-standalone.mysql.bz2
Web Dir: [/home/ufundo/Code/civicrm/civicrm-buildkit/build/build-0/web]
Output Dir: [/home/ufundo/Code/civicrm/civicrm-buildkit/build/build-0/.civibuild/debug]
Database Name: [build0civi_5wtdw]

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Input [/home/ufundo/Code/civicrm/civicrm-buildkit/vendor/civicrm/upgrade-test/databases_standalone/5.77.0-standalone-clean-mysql57.mysql.bz2]
Output [/home/ufundo/Code/civicrm/civicrm-buildkit/build/build-0/.civibuild/debug/5.77.0-standalone-clean-mysql57.mysql.bz2.out] [/home/ufundo/Code/civicrm/civicrm-buildkit/build/build-0/.civibuild/debug/5.77.0-standalone-clean-mysql57.mysql.bz2.log]

Dropping civicrm_* views from database build0civi_5wtdw

Dropping civicrm_* tables from database build0civi_5wtdw

Dropping civicrm_* functions from database build0civi_5wtdw

Loading database build0civi_5wtdw

Upgrading database build0civi_5wtdw


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Input [/home/ufundo/Code/civicrm/civicrm-buildkit/vendor/civicrm/upgrade-test/databases_standalone/5.77.0-standalone.mysql.bz2]
Output [/home/ufundo/Code/civicrm/civicrm-buildkit/build/build-0/.civibuild/debug/5.77.0-standalone.mysql.bz2.out] [/home/ufundo/Code/civicrm/civicrm-buildkit/build/build-0/.civibuild/debug/5.77.0-standalone.mysql.bz2.log]

Dropping civicrm_* views from database build0civi_5wtdw

Dropping civicrm_* tables from database build0civi_5wtdw

Dropping civicrm_* functions from database build0civi_5wtdw

Loading database build0civi_5wtdw
ERROR 1273 (HY000) at line 313: Unknown collation: 'utf8mb4_0900_ai_ci'

Upgrading database build0civi_5wtdw

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Summary
5.77.0-standalone-clean-mysql57.mysql.bz2	OK
5.77.0-standalone.mysql.bz2	ERROR
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(Upgrading to 5.78 because we the upgrade is actually broken on master)